You would be appalled, if so and so decided to sit next to the really beautiful girl, whose fiance had not taken his seat yet and so and so refused to move? Or some uninvited crasher or three take the seats meant for your oldest friends, or your cousin and is then removed ? Well bless your heart.
There are different rules for different kinds of weddings and if you had one ( which you didn't and I guess never would have, but stick with me...), which was a sit down whatever and were being charged per person and the food etc. had all been made, with no spare ones and a crasher or several came, you would be appalled if they were found and ousted ? Wouldn't you be MORE appalled by unconvincing your invited guests?
And yes,"and guest" without naming the person, is frowned upon.
The trouble with you is, you have to exaggerate so much to make your points valid. These are wedding guests we're managing, not a third grade class.